The Bedsheet is obtained from the innkeeper of Port Phasmatys during the Ghosts Ahoy quest to be given to Robin in a nearby room. This is possible even after the quest is complete, and the drop trick can be used to acquire multiple bedsheets. It is worn in the head slot.

Although it is brown when received, it can be changed to a light green colour by covering it in ectoplasm. To do this, players must dip it into the pool of slime on the bottom floor of the cavern beneath the Ectofuntus or dip it into a bucket of slime collected from the pool. Although this is supposed to make you resemble a ghost, when talking to residents of the port, they will merely joke at you.

When worn, the bedsheet makes the player resemble a classic "bedsheet" ghost. The bedsheet is not wearable in any other place than Port Phasmatys; attempting to do so will result in receiving a message, stating: "I'll only wear the bedsheet inside Port Phasmatys."

It is impossible to charter a ship while you are wearing a bedsheet.

Attempting to home teleport results in the message: "Please remove your ghost disguise before teleporting." However teleporting with, for example, the Desert Amulet 3, will teleport you but unequip the bedsheet.